1. Field
Embodiments of the present disclosure relate to an electric brake system, and more particularly, to an electric brake system generating a braking force using an electrical signal corresponding to a displacement of a brake pedal.
2. Description of the Related Art
A brake system for braking is necessarily mounted on a vehicle, and a variety of systems for providing stronger and more stable braking have been proposed recently.
For example, there are brake systems including an anti-lock brake system (ABS) for preventing a wheel from sliding while braking, a brake traction control system (BTCS) for preventing a driving wheel from slipping when a vehicle is unintentionally or intentionally accelerated, an electronic stability control system (ESC) for stably maintaining a driving state of a vehicle by combining an ABS with traction control to control hydraulic pressure of a brake, and the like.
Generally, an electric brake system includes a hydraulic pressure supply device which receives a braking intent of a driver in the form of an electrical signal from a pedal displacement sensor which senses a displacement of a brake pedal when the driver steps on the brake pedal and then supplies hydraulic pressure to a wheel cylinder.
An electric brake system provided with such a hydraulic pressure supply device is disclosed in European Registered Patent No. EP 2 520 473. According to the disclosure in that document, the hydraulic pressure supply device is configured such that a motor is activated according to a pedal effort of a brake pedal to generate braking pressure. At this point, the braking pressure is generated by converting a rotational force of the motor into a rectilinear movement to pressurize a piston.
Also, the electric brake system includes a simulation device capable of providing a driver with a reaction force according to the pedal effort of the brake pedal. At this point, the simulation device is connected to an oil reservoir, and a simulator valve is installed at an oil flow path which connects the simulation device to the oil reservoir.
Meanwhile, when hydraulic pressure is not generated by the hydraulic pressure supply device and hydraulic pressure, which is discharged from a master cylinder according to a pedal effort of the driver, is directly delivered to a wheel cylinder, the simulator valve is closed such that the hydraulic pressure delivered from the master cylinder is prevented from leaking.
However, when a leak occurs in the simulator valve, a dangerous situation may be caused by a braking force intended by the driver not being generated, and also production of high-quality products can be interrupted due to degradation of a feeling in terms of a pedal effort of braking.